Measuring intervention effects in children with ASD: The use of specific and global outcome measures A. Nordahl-Hansen 1, S. Fletcher-Watson 2, H. McConachie 4, & A. Kaale 1 University of Oslo, 2 University of Edinburgh, 3 Newcastle University 4 Oslo University Hospital Contact: Anders Nordahl-Hansen: Background Results Objectives References Conclusion Method 1. Green, J., Charman, T., McConachie, H., Aldred, C., Slonims, V., Howlin, P. … the PACT consortium. (2010). Parent- mediated communication focused treatment in children with autism (PACT): A controlled randomised controlled trial. The Lancet, 375, Yoder, P. J., Bottema-Beutel, K., Woynaroski, T., Chandrasekhar, R., & Sandbank, M. (2014). Social communication intervention effects vary by dependent variable type in pre-schoolers with autism spectrum disorders. Evidence-Based Communication Assessment and Intervention, 7, Grzadzinski, R., Carr, T., Colombi, C., McGuire, K., Dufek, S., & Lord, C. (in preparation). Development of a measure to identify change in ASD behaviors: Preliminary reliability and validity of the Brief Observation of Social Communication Change (BOSCC) 4. Bakeman, R., & Adamson, L. B. (1984). Coordinating attention to people and objects in mother-infant and peer-infant interaction. Child Development, 55, Kaale, A., Fagerland, M.W., Martinsen, E.W., & Smith, L. (2014). Preschool-based social communication treatment for children with autism: 12-month follow-up of a randomized trial. Journal of the American Academy for Child and Adolescent Psychiatry, 53, Jacobson, N. S., & Truax, P. (1991). Clinical significance: a statistical approach to defining meaningful change in psychotherapy research. Journal of Consulting and Clinical Psychology, 59, Fletcher-Watson, S., O’Hare, A., Pain, H., Petrou, A., & McConachie, H. (2013). Click-East: a randomised controlled trial of a new iPad-based social attention intervention for toddlers and pre-schoolers with autism. Developmental Medicine and Child Neurology, 55 (Suppl s2), PS9.3, p17.. Acknowledgements: The authors thanks the children and parents for their participation and COST ESSEA for financial support Outcome measures in social-communication interventions are often closely related to the intervention targets. Adding global outcome measures would strengthen validity of conclusions as to whether interventions also impact behaviours beyond treatment targets 1,2. There is a need for more knowledge of the relationship between specific and global outcome measures for use in evaluation of interventions targeting young children with ASD. The children in the intervention group had a mean change of time in joint engagement of 13.8% compared to -1.3% for the control group (p= 0.013, d= 0.67). The differences between control and intervention group did not reach significance for BOSCC social- and total –change scores (Table 1). McNemar’s test showed there was a statistical significant distribution of the two measures (p= 0.004, 95% CI = 1.50, 10.65). Our findings are in concurrence with earlier studies indicating that change in skills closely related to intervention targets may be apparent where more global change is not 1,2. More investigations using longitudinal designs are needed to assess whether, with time, treatment effects seen in proximal measures can also deliver downstream effects on measures of global change. Thus, the use of multiple outcome measures, specific and global, can elucidate important mechanisms and potential pathways from intervention to global change. To investigate whether a global ASD symptom measure; the Brief Observation of Social Communication Change 3 (BOSCC) and a more specific measurement procedure; Joint engagement states coding 4 (JE) identified similar group-level treatment effects. 59 children (2-4 year) diagnosed with autistic disorder who participated in a randomized controlled trial testing the effect of a brief social-communication intervention 5 were assessed with the JE and a preliminary version of BOSCC. Group differences in JE and BOSCC change scores (baseline- to post–intervention) were analysed using independent samples t- tests and effect size estimates (Cohen’s d). A reliable change index 6 (RCI) were calculated to analyse difference in distribution of change between measures using McNemar test of correlated proportions. Inter-rater reliability (IRR) for JE coding was high (ICC=.94). IRR for BOSCC was done on a separate sample 7 with ICCs of.989 for BOSCC total and.986 for BOSCC social communication sub-total scores.